This invention pertains to apparatus for directing a confined sheet-like spray of water onto the ground-contacting surface of a roller in a ground-compacting vehicle, or the like.
In the laying of various surfaces, such as an asphalt concrete surface for a road or a parking lot, what is known as a road roller vehicle is often used for final compacting and densifying of the concrete. Such a vehicle usually takes the form of a frame, in some instances a two-piece hinged frame, mounted for travel on a pair of rollers that are weighted, which rollers produce the compacting action as the vehicle moves over the ground. Typically, water is sprayed onto the outside surfaces of the rollers during operation in order to prevent concrete from sticking to them.
The present invention focuses on a unique arrangement for wetting the outside surfaces of such rollers, which arrangement is intended to avoid some of the problems and disadvantages that have been encountered with conventional wetting apparatus. More specifically, the usual road roller vehicle contains one or more tanks for holding water, with these tanks being connected to a pumping apparatus which in turn is connected to nozzles that direct sprays of water onto the surfaces of rollers. A conventional nozzle arrangement would include a plurality of nozzles distributed along a pipe which is mounted along a line that substantially parallels the rotational axis of a roller.
One of the problems which has been encountered in the past is that existing water-spray systems use a substantial amount of water, and it is often necessary during a work shift for an operator to refill the water tanks. Often when this is done out on the job various kinds of dirt get into the tanks, and after a period of time may foul a pump and may cause clogging of the nozzles. Another drawback is that the time required for refilling of water tanks is, essentially, down-time for the equipment. Hence, it increases the cost of doing a job.
Still another disadvantage is that when the road roller vehicle moves along an inclined surface where the rollers are tilted along their rotational axes, water distribution by conventional gravity feed water-spray systems is not uniform. In other words, one end of a roller may receive water and the other end no water. Still a further consideration is that a pumping system with multiple nozzles is quite costly, and thus adds to the overall expense of a vehicle. Further, nozzles can represent a considerable maintenance problem, particularly where clogging and fouling result from the use of dirty water.
Therefore, a general object of the present invention, as has been suggested earlier, is to provide a unique water-spray system for use in conjunction with a road roller vehicle, and the like, which system avoids these various drawbacks of prior art systems.
According to a preferred embodiment of the invention, what is proposed is a flat rotary disk which is driven by a small motor, and is located on the underside of a vehicle's frame, with the disk being disposed in a plane which substantially parallels the plane of the ground underlying the vehicle. Water tanks on the vehicle communicate, through gravity flow, with this disk by way of conduits which simply extend from the tanks to points immediately overlying the disk. As will become more fully explained, the particular embodiment of the invention which is illustrated and described herein includes a pair of such conduits, with solenoid-operated valves provided for allowing or shutting off the flow of water.
During operation of the proposed system, the disk is rotated by the motor, and water is spilled onto the top surface of the disk, at a selected rate, by one or more of the conduits. This action results in a sheet-like spray of water being ejected from the disk as it spins, with this spray being directable onto the ground-contacting surfaces of the rollers. Associated with the disk is a housing which is configured, as will be described, to confine the spaces around the disk through which water may be ejected to escape the housing. In particular, two spaces are defined herein for the escape of water, which spaces are sized so that sprays of water are directed in a laterally confined manner onto the front and rear rollers. Such sprays, where they strike the rollers, have a width which is substantially the same as the lengths of the rollers.
With such a system, the problems of pumping, pump fouling, and nozzle clogging are completely avoided. Gravity flow is used for flowing the water. A single device, the rotary disk, mounted intermediate the front and rear rollers functions to provide an operative spray of water for both of the rollers. This spray is confined so that it does not appreciably overspray the rollers, i.e., spray beyond the ends of the rollers, and hence water wastage is held to a minimum. With the rotational plane of the rotary disk remaining at all times substantially parallel to the plane of the underlying ground, tilting of a roller during operation will not result in parts of the drums not being lubricated.
These and other objects and advantages which are attained by the invention will become more fully apparent as the description which now follows is read in conjunction with the accompanying drawings.